Questions about cutting a solid.

[DWAS]

Hi all. I am using version X4 and am in MastercamU. Does anyone know what the difference is between an extrude "create body" and extrude "create boss"? I understand what a boss is, and realize that you must have a solid body already to create a boss. But, if i create a rectangle solid and then draw a circle on one of its planes and extrude it as a body and then then undo the operation and redraw it as a boss instead, I see no visible difference. I end up with the same thing in the end. What exactly is the difference as far as the software is concerned.

 

Also, relating to the above topic, I have the same question with comparison of an extrude "cut body" vs. boolean remove, vs. a sweep that would cut body. Does anyone know what the exact difference is between these 3 operations?

[DWAS]

??? anybody

[DWAS]

did i post this in the wrong section or something?

[htm01]

not something i ever questioned, there is most often more than 1 way to do something.

[Mike S @ S4A]

boss vs. body -

creating two bodies is creating two bodies (check the solids tree in the op mgr)

adding a boss to a body adds a feature on an existing body; thus one entity in the tree.

think about it

[tedly]

boss is any lump on body.

[MotorCityMinion]

You're comparing apples and oranges here but I'll try to explain it with out any teaching credentials . This will be my first post with pictures on the new forum, so I'll put some effort into it.

 

Using a boolean remove is an added step, can clutter up the solids tree needlessly, and results in more time spent making the model. It is best to use the Boolean features sparingly. Usually it's used when your working with two separate sold bodies. Why 2 bodies? Maybe you imported 1 of the bodies and need to use it, or a portion of it, to add to, or remove from your existing solid. Some complex solids are easier to create after multiple (Separate) solid bodies have been made, then removed or added to the main solid. Booleans are also used when you need to make multiple bodies of a solid for an Xform function such as Mirror or Translate to speed up the creation of the Model. More on that in a few.

 

Extrude is a linear function, that is to say it will not follow a curved path. This is almost always the first step, (but not necessarily), in creating most models. Consider it the main body of the model. In Mastercam, extruded features (Shapes), must be flat, that is to say all the drawing features of the particular shape must lie in the same plane. Try to extrude the side of a part that will yield the most features to describe that part without creating problems later on in your model. With more complex models, knowing what side to extrude first and how many features to put in that extrusion is a matter of experience. Choosing the wrong face to start with can result in major complications later on or even catastrophic failure forcing you to start from scratch. If no other solids exist on the current visible levels, you will not have the option to cut or add boss. You can only cut or add boss as an extrude if a Solid is already created and exist on a visible level, otherwise it just becomes a new and separate solid body.

 

EX 1: Notice in the following drawing that all the features that I'm about to extrude lie flat in their own separate planes and that the green and the blue do not intersect the model (although they could if I needed them to) that resulted from the first extrusion of the grey profile. The grey is in the right plane and the main, or first extrude, green is in the front and is a cut, and the blue is rotated to a compound angle and is a add boss. Also take note that only 1 solid body is created in these 3 operations and that a boolean op cannot be performed here nor do we want to use that function. We don't need 2 or 3 separate bodys as that would just create more work and a messy Solids tree.

 

 

Sweeps are used when a profile needs to follow a path that is curvy. Both a profile and path are required. Do not use a single straight line as your path because this would result in the same exact shape as an extrude and needlessly adds an extra step. Sweeps can get complicated quickly. You can only cut or add boss as a Sweep if a Solid is already created and exist on a visible level.

Being a little silly here but the next pics shows 2 sweeps, the second being a add boss, using two of the same profiles that I used for the extrude. Splines were created for the path.

 

 

Now back to the Boolean op. Since you can't Xform a individual operation within a solid body, I'll create separate solid bodies so that I can mirror them, then use the Boolean Remove function to save some work. The blue geometry in the pictures are what im after.

 

 

Here are the results after the Boolean Remove, and the finished part turned into surfaces so that I could color the individual faces for clarity. (Solid face coloring coming soon in X5 so they say)

Take note of the solids tree and level manager, everything is named for clarity. It also helps when others are trying to follow what you've done.

 

The finished part:

 

I hope this anwsers some of your questions, and WOW, the new forum is speedy. MCM.

[Joseph]

Now that was great. Very clear with the examples, and I'm sure a lot of work.

 

Thanks